DNA ligase



DNA ligase (LigD) is an enzyme which repairs single-stranded breaks in a double-stranded DNA. LigD is activated, in a species-dependent manner, by hydrolysis of ATP or NAD+. Mamlian LigD I ligates the nascent DNA of the lagging strand; LigD III complexes with XRCC1 in the process of nucleotide excision repair; LigD IV complexes with XRCC4 and catalyzes the last step in the non-homologous DNA end joining. See detailed 1x9n for details of human DNA ligase I.

3D Structures of DNA ligase
Update June 2011

ATP-dependent LigD
3p4h – LigD N-terminal – Candidatus korarchaeum cryptofilum

3gde – LigD – Archaeoglobus fulgidus

2hiv – SsLigD – Sulfolobus solfataricus

2hix - SsLigD + ATP

2cfm - LigD + AMP – Pyrococcus furiosus

2fao - PaLigD polymerase domain – Pseudomonas aeruginosa

2faq, 2far - PaLigD polymerase domain + ATP + Mn

1a0i – LigD + ATP – Bacteriophage T7

NAD+-dependent LigD
3jsl, 3jsn - LigD adenylation domain – Staphylococcus aureus

3ba8, 3ba9,  3baa,  3bab,  3bac - EfLigD adenylation domain + inhibitor – Enterococcus faecalis

1ta8, 1tae - EfLigD adenylation domain

1zau - LigD adenylation domain – Mycobacterium tuberculosis

1v9p, 1dgs – LigD – Thermus filiformis

1b04 – LigD adenylation domain (mutant) – Geobacillus stearothermophilus

LigD
2q2t – CvLigD + DNA + AMP + CMP – Chlorella virus

2q2u, 1p8l,  1fvi - CvLigD + DNA + mononucleotide

2owo – LigD + DNA + AMP + CMP – Escherichia coli

3qwu – LigD – Aquifex aeolicus

3pn1 – LigD adenylation domain + inhibitor – Haemophilus influenzae

1l7b – LigD BRCT domain – Thermus thermophilus - NMR

Mammalian LigD I
1x9n – hLigD I + DNA + AMP + CMP – human

2od8 – LigD I residues 32-53 + PCNA

Mammalian LigD III
3l2p – hLigD III residues 257-833 + DNA

1uw0 - hLigD III zinc-finger domain residues 1-117 – NMR

1imo, 1in1 - hLigD III BRCTdomain – NMR

Mammalian LigD IV
3ii6, 1ik9 – hLigD IV C-terminal BRCT domains + DNA repair protein XRCC4

2e2w - hLigD IV BRCT domain - NMR

1z56 – LigD IV + ligase interacting factor 1 - yeast